1. Field of the Invention
The present invention relates generally to devices and methods for the percutaneous closure of body lumens. More particularly, the present invention relates to devices and methods for the percutaneous closure of arterial and venous puncture sites, which are usually accessible only through a tissue tract.
A number of diagnostic and interventional vascular procedures are now performed transluminally, where a catheter is introduced to the vascular system at a convenient access location and guided through the vascular system to a target location using established techniques. Such procedures require vascular access which is usually established using the well known Seldinger technique, as described, for example, in William Grossman's "Cardiac Catheterization and Angiography," 3rd Ed., Lea and Febiger, Philadelphia, 1986, incorporated herein by reference.
When vascular access is no longer required, the introducer sheath must be removed and bleeding at the puncture site stopped. One common approach to attempt providing hemostasis (the cessation of bleeding) is to apply external force near and upstream from the puncture site, typically by manual or "digital" compression. This approach suffers from a number of disadvantages. It is time-consuming, frequently requiring one-half hour or more of compression before hemostasis is assured. This procedure is uncomfortable for the patient and frequently requires administering analgesics to be tolerable. Moreover, the application of excessive pressure can at times totally occlude the underlying blood vessel, resulting in ischemia and/or thrombosis. Following manual compression the patient is required to remain recumbent for at least six and at times as long as eighteen hours under close observation to assure continued hemostasis. During this time renewed bleeding may occur resulting in bleeding through the tract, hematoma and/or pseudoaneurism formation as well as arteriovenous fistula formation. These complications may require blood transfusion and/or surgical intervention. The incidence of these complications increases when the sheath size is increased and when the patient is anticoagulated. It is clear that the standard technique for arterial closure can be risky, and is expensive and onerous to the patient. While the risk of such conditions can be reduced by using highly trained individuals, such use is both expensive and inefficient.
To overcome the problems associated with manual compression, the use of bioabsorbable fasteners to stop bleeding has been proposed by several groups. Generally, these approaches rely on the placement of a thrombogenic and bioabsorbable material, such as collagen, at the superficial arterial wall over the puncture site. While potentially effective, this approach suffers from a number of problems. It can be difficult to properly locate the interface of the overlying tissue and the adventitial surface of the blood vessel, and locating the fastener too far from that surface can result in failure to provide hemostasis and subsequent hematoma and/or pseudo aneurism formation. Conversely, if the fastener intrudes into the arterial lumen, intravascular clots and/or collagen pieces with thrombus attached can form and embolize downstream causing vascular occlusion. Also, thrombus formation on the surface of a fastener protruding into the lumen can cause a stenosis which can obstruct normal blood flow. Other possible complications include infection as well as adverse reactions to the collagen implant.
For these reasons, it would be desirable to provide improved devices and methods to seal body lumen puncture sites. It would be particularly desirable to provide percutaneous devices and methods for suturing the puncture sites required for percutaneous vascular procedures.
2. Description of the Background Art
Devices capable of delivering pairs of needles to various tissue locations are described in the following patents and patent applications: U.S. Pat. Nos. 4,493,323 and 659,422; European patent application 140 557; and U.S.S.R patent applications 1174-036-A and 1093-329-A. Other suturing and ligating devices are described in U.S. Pat. Nos. 3,665,926; 2,959,172; and 2,646,045. Devices for sealing percutaneous vascular penetrations using various fastener structures are described in U.S. Pat. Nos. 5,061,274; 5,021,059; 4,929,246; 4,890,612; 4,852,568; 4,744,364; 4,587,969; and 3,939,820. Collagen fastener sealing devices are under commercial development by Datascope Corp., Montvale, N.J., and Kensey Nash Corporation, Exton, Pa.